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A372045
Positions of records in A030000.
2
0, 7, 11, 22, 50, 61, 78, 100, 121, 122, 127, 155, 263, 548, 1000, 1002, 1003, 1016, 1559, 1583, 1877, 3087, 9634, 10001, 10029, 10199, 10620, 25672, 100002, 100005, 100085, 100116, 100457, 100956, 101597, 101624, 114323, 191974, 1000004, 1000006, 1000055, 1000227, 1000517, 1000717, 1000728, 1027986, 1098714, 1127153, 1429848, 3659369
OFFSET
1,2
EXAMPLE
From David A. Corneth, Apr 17 2024: (Start)
0 is a term as it is the least nonnegative integer and A030000(0) = 10.
7 is a term after 0 as 7 is the first number that is first seen at a k such that 2^k contains 7 as a substring (namely at k = 15). (End)
MATHEMATICA
d2k[k_] := d2k[k] = IntegerString[2^k];
A030000[n_] := Block[{d = IntegerString[n], k = -1}, While[StringFreeQ[d2k[++k], d]]; k];
Block[{upto = 10000, n = -1, a, r = -1}, Reap[While[++n <= upto, If[(a = A030000[n]) > r, r = a; Sow[n]]]][[2, 1]]]
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Paolo Xausa, Apr 17 2024
EXTENSIONS
More terms from David A. Corneth, Apr 17 2024
STATUS
approved